Johnstone sums up this system as follows:
"Draining according to Elkington's principles depends chiefly upon three things:
"1. Upon discovering the main spring, or source of the evil.
"2. Upon taking the subterraneous bearings: and,
"3dly. By making use of the auger to reach and tap the springs, when the depth of the drain is not sufficient for that purpose.
"The first thing, therefore, to be observed is, by examining the adjoining high grounds, to discover what strata they are composed of; and then to ascertain, as nearly as possible, the inclination of these strata, and their connection with the ground to be drained, and thereby to judge at what place the level of the spring comes nearest to where the water can be cut off, and most readily discharged. The surest way of ascertaining the lay, or inclination, of the different strata, is, by examining the bed of the nearest streams, and the edges of the banks that are cut through by the water; and any pits, wells, or quarries that may be in the neighborhood. After the main spring has been thus discovered, the next thing is, to ascertain a line on the same level, to one or both sides of it, in which the drain may be conducted, which is one of the most important parts of the operation, and one on which the art of draining in a scientific manner essentially depends.
"Lastly, the use of the auger, which, in many cases, is the sine qua non of the business, is to reach and tap the spring when the depth of the drain does not reach it: where the level of the outlet will not admit of its being cut to a greater depth; and where the expense of such cutting would be great, and the execution of it difficult.
"According to these principles, this system of draining has been attended with extraordinary consequences, not only in laying the land dry in the vicinity of the drain, but also springs, wells, and wet ground, at a considerable distance, with which there was no apparent connection."